The tag thing is abit different then Designing for your income, Tagging is more abstract and trying to see if it will come out nicely while designing for hire is a real different thing because you need to make something someone else likes.
I'm going to CnC you like any other:
Almost never use more then 1 render/stock because a tag is powered by the "focal point" which draws the attention example:
My signature draws the attention to the fact because it is lightened properly and the rest is abit darker and all the effects happen in this place.
Next thing:
"Flow"
This tag I made creates a flow going just a few directions.
people try to create a flow by smudging adding c4d's blurring stuff brushing clonetooling etc etc etc.
This is what your signature lacks atm, You apparently have the photoshop skills but almost no tag skills atm, and it's going to take you quite abit of time to get the hand of it.
(please excuse me from the spelling mistakes I'm really busy and I tried to type this out fast.)